Bombay High Court: has , held that to declare land as private forest under Maharashtra Private Forest (Acquisition) Act, 1975, it is necessary for the land to fall under the ambit of ‘private forest’ under Section 2 (f) and notice has to be issued to the owner and to all other persons having an interest in such land, calling on them to show cause why such declaration should not be made. ...

2) Section 21 of the Act, 1975 mandates the Collector or any officer authorised in this behalf by State Government, to issue a notice to the owner and to all other persons having an interest in such land, calling on them to show cause why such declaration should not be made....

3) you can file writ in HC against declaration of your land as private forest land 

You will have to file writ petition in HC and in light of SC judgment HC would remand case to Collector to decide whether land falls under ambit of forest  land 

Dear client,

In India, state-specific laws frequently regulate matters pertaining to property. You have legal options to make corrections if your ancestral property has been mistakenly labeled as private forest land. First, compile all pertinent data, such as the town planning zone certificate from 1997, the 7/12 and "pher phar" records, and any other proof that the land is still agricultural. Make contact with the District Collector, presenting this documentation and elucidating the disparity in the land's classification. As a public servant, the District Collector is qualified to examine and correct such mistakes. Should the problem continue, you can think about bringing a writ suit against the incorrect designation in the High Court under Article 226 of the Indian Constitution. Though it could take some time, this procedure is legal remedy to seek justice.

Hope this helps you.

Private Forest means a forest which is not the property of the GOVERNMENT or over which the State has no proprietary rights or to the whole or any part of the forest produce of which the State is not entitled.

You have documentary evidences to prove that this is your ancestral property. 

The town planning department has so far not issued any notice but have orally informed you. 

Since the revenue records also do not say that this is a private forest land,  you don't need to be concerned about it for now. 

You may gather the documentary evidences and secure them to challenge the future issues if any.

District collector has not declared this to be a forest land hence there's no point in approaching him nor high court with a writ petition. You may wait and watch the developments. 

Planning officer is lying just for the sake of bribe. Tell him to show document which mentioning it private forest. or get under RTI, land record and nature of land. 

If it’s declared private forest after your purchase then you can claim compensation 

If it has been acquired with a notification then the date of notification would be taken for consideration to assess the value of the property being assessed.

Hence the notification date or the date of acquisition is important

Compensation would be at current market rates and not the rates fixed in 1976 

Dear client,

The Collector typically decides the compensation after taking into account market value, current land prices, and other pertinent variables. Rather than using rates from the year the act was passed, the compensation ought to be based on current market rates. The Collector has the power to make a decision in this case. It might be necessary for you to submit a formal application to the Collector along with supporting documentation and proof of the 1997 agricultural zone classification.

Hope this helps you.

Then you can proceed for compensation